Three-dimensional tire sipe

ABSTRACT

Various embodiments of a tire having a three-dimensional tire sipe are disclosed. In one embodiment, a tire sipe used in a tire is provided, the tire sipe comprising: a radially inner sipe taper portion having a radially inner sipe width W3 and a radially inner sipe transition width W4, wherein the radially inner sipe width W3 is greater than the radially inner sipe transition width W4; a radially outer sipe taper portion having a radially outer sipe width W1 and a radially outer sipe transition width W2, wherein the radially outer sipe width W1 is greater than the radially outer sipe transition width W2; and a sipe radially central portion having a plurality of individual sipe radially angled portions oriented in a zig-zag pattern, wherein the sipe radially central portion is oriented radially between the radially inner sipe taper portion and the radially outer sipe taper portion.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from U.S. Provisional PatentApplication No. 62/367,143, filed on Jul. 27, 2016, which isincorporated by reference herein in its entirety.

BACKGROUND

Tires for use on vehicles may comprise a tread featuring sipes. Thepresence of sipes in a tire tread may create more surface edges toengage a roadway, which may increase traction in adverse roadconditions. For example, a tire tread including sipes may perform betterin icy, snowy, or wet road conditions than a tire tread not includingsipes. Likewise, the more sipes a tire has, the better traction it mayexhibit in adverse road conditions.

However, the addition of sipes to a tire tread block may reduce blockstiffness, which may result in undesirable irregular wear patterns inthe tire and a decrease in tire performance in dry road conditions(i.e., non-adverse conditions). Increasing the number of sipes in a tiretread block may relate to a decrease in stiffness of that tire treadblock.

What is needed is a tire sipe configured to provide adequate traction inadverse road conditions, while maintaining the required stiffness fordry road conditions, and while resisting irregular wear patterns.

SUMMARY

In one embodiment, a tire sipe used in a tire is provided, the tire sipecomprising: a radially inner sipe taper portion having a radially innersipe width W3 and a radially inner sipe transition width W4, wherein theradially inner sipe width W3 is greater than the radially inner sipetransition width W4; a radially outer sipe taper portion having aradially outer sipe width W1 and a radially outer sipe transition widthW2, wherein the radially outer sipe width W1 is greater than theradially outer sipe transition width W2; and a sipe radially centralportion having a plurality of individual sipe radially angled portionsoriented in a zig-zag pattern, wherein the sipe radially central portionis oriented radially between the radially inner sipe taper portion andthe radially outer sipe taper portion.

In another embodiment, a tire sipe used in a tire is provided, the tiresipe comprising: a radially inner sipe taper portion having a radiallyinner sipe width W3 and a radially inner sipe transition width W4,wherein the radially inner sipe width W3 is greater than the radiallyinner sipe transition width W4; and a sipe radially central portionhaving a plurality of individual sipe radially angled portions orientedin a zig-zag pattern, wherein the sipe radially central portion isoriented radially outwardly of the radially inner sipe taper portion.

In another embodiment, a tire sipe used in a tire is provided, the tiresipe comprising:

a radially outer sipe taper portion having a radially outer sipe widthW1 and a radially outer sipe transition width W2, wherein the radiallyouter sipe width W1 is greater than the radially outer sipe transitionwidth W2; and a sipe radially central portion having a plurality ofindividual sipe radially angled portions oriented in a zig-zag pattern,wherein the sipe radially central portion is oriented radially inwardlyof the radially outer sipe taper portion.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying figures, which are incorporated in and constitute apart of the specification, illustrate various example configurations,and are used merely to illustrate various example embodiments. In thefigures, like elements bear like reference numerals.

FIG. 1 illustrates a plan view of an example embodiment of a tire tread100 having a three-dimensional tire sipe.

FIG. 2 illustrates a perspective view of an example embodiment of a tiretread block 202 having a three-dimensional tire sipe.

FIG. 3 illustrates a sectional view of an example embodiment of a tiretread block 302 having a three-dimensional tire sipe.

FIG. 4 illustrates an elevational view of an example embodiment of atire tread block 402 having a three-dimensional tire sipe.

FIG. 5 illustrates an elevational view of an example embodiment of atire tread block 502 having a three-dimensional tire sipe.

FIG. 6 illustrates a partial perspective view of an example embodimentof a tire tread block 602 having a three-dimensional tire sipe.

FIG. 7A illustrates a plan view of an example embodiment of a tire sipeblade 780 for molding a three-dimensional tire sipe.

FIG. 7B illustrates a side elevational view of an example embodiment oftire sipe blade 780 for molding a three-dimensional tire sipe.

FIG. 7C illustrates a front elevational view of an example embodiment oftire sipe blade 780 for molding a three-dimensional tire sipe.

FIG. 7D illustrates a perspective view of an example embodiment of tiresipe blade 780 for molding a three-dimensional tire sipe.

FIG. 8 illustrates a force-displacement curve for a tire tread blockfeaturing a three-dimensional tire sipe versus a tire tread blockfeaturing a two-dimensional tire sipe.

FIG. 9 illustrates a perspective view of an example embodiment of a tiretread block 902 having a three-dimensional tire sipe.

FIG. 10 illustrates a perspective view of a prior art tire tread block1090 having a two-dimensional tire sipe.

FIG. 11 illustrates a graph comparing various properties of a tireutilizing various tire sipe styles.

DETAILED DESCRIPTION

Tires not intended for operation on smooth, dry surfaces typicallycomprise a tread pattern, including a least one groove, at least onerib, and/or a plurality of tread blocks. Tires intended for operation ininclement conditions, including for example icy or snowy conditions, mayadditionally comprise a plurality of sipes in the tire tread. Theaddition of sipes in the tire tread may result in more surface edges inthe tire tread for engagement with the icy or snowy roadway.

Increasing the length of a sipe, such as orienting the sipe in a“zig-zag” pattern, may increase the amount of cutting edges available toengage snowy, icy, and/or wet road surfaces.

Orienting the sipe in a zig-zag pattern in at least one of the lateraldirection of the tire and the radial direction of the tire, may allowopposing walls of the sipe to at least partially engage one another in ahigh friction, or locking, manner to maintain a desired stiffness of thetire tread block or tire tread rib. Maintaining a specified level ofstiffness in the tire tread may mitigate or eliminate irregular wearpatterns. Maintaining a specified level of stiffness in the tire treadmay improve stopping distance of the tire. Maintaining a specified levelof stiffness in the tire tread may improve traction of the tire.

Traditional sipes comprise substantially radially-oriented, narrow slitsextending from a tread surface into the tread. These traditional sipestypically include straight, parallel walls.

FIG. 1 illustrates a plan view of an example embodiment of a tire tread100 having at least one three-dimensional tire sipe 104. Tire tread 100may include a plurality of tire tread blocks 102. At least one of theplurality of tire tread blocks 102 may include at least one tire sipe104.

Tire tread 100 may include at least one groove 106. At least one groove106 may be a circumferential groove. At least one groove 106 may be agroove inclined relative to the circumferential direction (as indicatedby the X-axis as identified in FIG. 1 ) and/or to a centerline of tiretread 100. At least one groove 106 may be a groove substantiallyparallel to a centerline of tire tread 100. At least one groove 106 maybe oriented substantially longitudinally. At least one groove 106 mayinclude a plurality of grooves oriented substantially circumferentially,substantially parallel to a centerline of a tire tread, inclinedrelative to the circumferential direction, or a combination of two ormore thereof.

Tire tread 100 may include at least one shoulder rib 108. Tire tread 100may include at least one intermediate rib 110. Tire tread 100 mayinclude at least one center rib 112. At least two of shoulder rib 108,intermediate rib 110, and center rib 112 may be separated by at leastone groove 106. Shoulder rib 108, intermediate rib 110, and center rib112 may each comprise a plurality of distinct tread blocks. Shoulder rib108, intermediate rib 110, and center rib 112 may each be solid ribs,not including distinct tread blocks. Alternatively, a least one ofshoulder rib 108, intermediate rib 110, and center rib 112 may comprisea plurality of distinct tread blocks, while at least one of shoulder rib108, intermediate rib 110, and center rib 112 may be a solid rib, notincluding distinct tread blocks. While FIG. 1 illustrates two shoulderribs 108, and two intermediate ribs 110, it is understood that the twoshoulder ribs 108 and/or the two intermediate ribs 110 may be differentfrom one another, respectively. While FIG. 1 illustrates two shoulderribs 108, two intermediate ribs 110, and one center rib 112, it isunderstood that this is an example tire tread 100, and that tire tread100 may include more or less ribs.

Shoulder rib 108 may comprise a plurality of shoulder blocks 114.Intermediate rib 110 may include a plurality of intermediate blocks 116.Center rib 112 may include a plurality of center blocks 118. Shoulderblocks 114, intermediate blocks 116, and center blocks 118 may make uptire tread blocks 102. Any of shoulder blocks 114, intermediate blocks116, and center blocks 118 may be distinct tread blocks. Any of shoulderblocks 114, intermediate blocks 116, and center blocks 118 may bedistinct tread blocks separated by at least one transverse groove 123.

At least one transverse groove 123 may be inclined relative to the axialdirection (as indicated by the Y-axis as identified in FIG. 1 ). Atleast one transverse groove 123 may be substantially parallel to theaxial direction. At least one transverse groove 123 may be inclinedrelative to the circumferential direction (as indicated by the X-axis asidentified in FIG. 1 ). At least one transverse groove 123 may connectto at least one groove 106. At least one transverse groove 123 may, insome instances, extend between two or more grooves 106.

Tire tread blocks 102 may include a radially outermost block surface120. Block surface 120 may include a road contact surface, which may bethat surface of tire tread block 102 that contacts a road surface duringoperation of a tire incorporating tire tread 100. At least one tire sipe104 may extend into tire tread block 102 from block surface 120.

Tire tread blocks 102 may include at least one block sidewall 122. Atleast one block sidewall 122 may be oriented substantially parallel tothe radial direction of the tire. At least one block sidewall 122 may beinclined relative to the radial direction of the tire. At least oneblock sidewall 122 may be oriented at or near at least one groove 106,at least one transverse groove 123, or a combination thereof.

At least one tire sipe 104 may open into at least one groove 106. Atleast one tire sipe 104 may open into at least one transverse groove123. At least one tire sipe 104 may open into at least one of groove 106and transverse groove 123.

FIG. 2 illustrates an example embodiment of a tire tread block 202having at least one three-dimensional tire sipe 204. Tire tread blocks202 may have a radially outermost block surface 220. Tire tread blocks202 may have at least one block sidewall 222.

Tire sipe 204 may extend into tire tread block 202 from block surface220. Tire sipe 204 may extend into tire tread block 202 from at leastone block sidewall 222. Tire sipe 204 may extend into tire tread block202 from both block surface 220 and at least one block sidewall 222.Tire sipe 204 may extend into tire tread block 202 from at least one ofblock surface 220 and block sidewall 222. It is understood that tiresipe 204 extending into tire tread block 202 from at least one of blocksurface 220 and block sidewall 222 means that tire sipe 204 opens intoat least one of block surface 220 and block sidewall 222.

Tire sipe 204 may have a substantially zig-zag shape at its intersectionwith at least one of block surface 220 and block sidewall 222. Tire sipe204 may have a substantially zig-zag shape at its intersection with bothof block surface 220 and block sidewall 222.

As illustrated in FIG. 2 , the X-axis may represent a circumferentialdirection, while the Y-axis may represent an axial direction, while theZ-axis may represent a radial direction.

FIG. 3 illustrates a sectional view of an example embodiment of a tiretread block 302 having a three-dimensional tire sipe 304. Tread block302 may include a radially outermost block surface 320. Tire sipe 304may open into block surface 320. Block surface 320 may be a road contactsurface. As such, tire sipe 304 may be in contact with a road surface.Tire sipe 304 may be operatively connected to a road surface. Tire sipe304 may engage a road surface. Tire sipe 304 may be operativelyconnected with an element on a road surface, including for example aliquid such as water, or a solid such as snow or ice.

Tire sipe 304 may include a radially inner sipe taper portion 324.Radially inner sipe taper portion 324 may include a tapered void thatdecreases in width as it progresses radially. Radially inner sipe taperportion 324 may include a greater width at its radially innermostportion, and a lesser width at its radially outermost portion. Radiallyinner sipe taper portion 324 may include a radially inner sipe width W3,and a radially inner sipe transition width W4. Width W3 may be greaterthan width W4, such that radially inner sipe taper portion 324 tapers intoward itself as it extends radially outwardly.

In one embodiment, width W3 may be about 0.60 mm, while width W4 may beabout 0.42 mm. In one embodiment, width W3 and W4 may be any of avariety of widths, as may be desired in any of various designs of tiresipe 304.

In one embodiment, width W3 may be between about 0.54 mm and about 0.66mm. In another embodiment, width W3 may be between about 0.48 mm andabout 0.72 mm. In another embodiment, width W3 may be between about 0.42mm and about 0.78 mm. In another embodiment, width W3 may have a rangecomprising the lower and upper limits of any of the various rangesrecited above, for example, a range between about 0.48 mm and about 0.78mm.

In one embodiment, width W4 may be between about 0.38 mm and about 0.46mm. In another embodiment, width W4 may be between about 0.33 mm andabout 0.50 mm. In another embodiment, width W4 may be between about 0.29mm and about 0.55 mm. In another embodiment, width W4 may have a rangecomprising the lower and upper limits of any of the various rangesrecited above, for example, a range between about 0.33 mm and about 0.55mm.

Width W4 may be about 70% of width W3. Width W3 may be about 143% ofwidth W4. In one embodiment, width W4 may be between about 65% and about75% of width W3. In another embodiment, width W4 may be between about60% and about 80% of width W3. In another embodiment, width W4 may bebetween about 55% and about 85% of width W3. In another embodiment,width W4 may be between about 60% and about 70% of width W3. In anotherembodiment, width W4 may be between about 70% and about 80% of width W3.In another embodiment, width W4 may be a percentage of width W3 within arange comprising the lower and upper limits of the various rangesrecited above, for example, a range between about 60% and about 70%.

Radially inner sipe taper portion 324 may include widths W3 and W4 thatare configured to provide adequate passageway in the base of tire sipe304 to increase a flow of a liquid along the base of tire sipe 304. Thatis, widths W3 and W4 may be selected to permit a desired flow of aliquid such as water through the base (radially innermost portion) oftire sipe 304. Radially inner sipe taper portion 324 may include widthsW3 and W4 that are configured to increase strength and/or stiffness of asipe blade used to mold tire sipe 304.

Tire sipe 304 may include a depth D1, measured in a radial direction(illustrated as the Z-axis). Depth D1 may be about 6.60 mm. In oneembodiment, depth D1 may be any of a variety of depths, as may bedesired in any of various designs of tire sipe 304. Radially inner sipetaper portion 324 may have a depth D5. Depth D5 may be about 2.60 mm. Inone embodiment, depth D5 may be any of a variety of depths, as may bedesired in any of various designs of tire sipe 304. Depth D5 may beabout 40% of depth D1. In one embodiment, depth D5 may be between about35% and about 45% of depth D1. In another embodiment, depth D5 may bebetween about 30% and about 50% of depth D1. In another embodiment,depth D5 may be between about 25% and about 55% of depth D1. In anotherembodiment, depth D5 may be a percentage of depth D1 within a rangecomprising the lower and upper limits of any of the various rangesrecited above, for example, a range between about 35% and about 55%.

Tire sipe 304 may have a depth D1 that extends radially inwardly to awear bar of the tire. Tire sipe 304 may have a depth D1 that extendsradially inwardly to a wear bar of the tire to maintain sipe edgedensity count through the entire recommend service life of a tire (basedon tread wear) having tire sipe 304. Maintaining sipe edge density countthrough the entire life of the tire having tire sipe 304 may maintain atleast one of snow performance and wet performance, for the entirerecommended service life of the tire (based on tread wear).

Tire sipe 304 may include a sipe radially central portion 326. Centralportion 326 may include a plurality of individual sipe radially angledportions, including for example, a first sipe radially angled portion328, a second sipe radially angled portion 330, a third sipe radiallyangled portion 332, and a fourth sipe radially angled portion 334.Central portion 326 may be comprised of a plurality of individual angledportions oriented in a zig-zag pattern.

First angled portion 328 may extend from the radially outermost portionof sipe taper portion 324, to the radially innermost portion of secondangled portion 330. Second angled portion 330 may extend from theradially outermost portion of first angled portion 328 to the radiallyinnermost portion of third angled portion 332. Third angled portion 332may extend from the radially outermost portion of second angled portion330 to the radially innermost portion of fourth angled portion 334.Fourth angled portion 334 may extend from the radially outermost portionof third angled portion 332 to the radially innermost portion of aradially outer sipe taper portion 336.

Each of first angled portion 328, second angled portion 330, thirdangled portion 332, and fourth angled portion 334 may be oriented at anangle A1 relative to the circumferential direction (illustrated by theX-axis). Angle A1 may be any of a variety of angles as may be desired inany of various designs of tire sipe 304. In one embodiment, angle A1 maybe about 45 degrees. In another embodiment, angle A1 may be betweenabout 40 degrees and about 50 degrees. In another embodiment, angle A1may be between about 36 degrees and about 54 degrees. In anotherembodiment, angle A1 may be between about 31 degrees and about 59degrees. In another embodiment, angle A1 may include a range comprisingthe lower and upper limits of any of the various ranges recited above,for example, a range between about 36 degrees and about 59 degrees.

Sipe radially central portion 326 may include a thickness T1. ThicknessT1 may be any of a variety of thicknesses as may be desired in any of avarious designs of tire sipe 304. In one embodiment, thickness T1 may beabout 0.30 mm. In another embodiment, thickness T1 may be between about0.25 mm and about 0.35 mm. In another embodiment, thickness T1 may bebetween about 0.20 mm and about 0.40 mm. In another embodiment,thickness T1 may be between about 0.15 mm and about 0.45 mm. In anotherembodiment, thickness T1 may include a range comprising the lower andupper limits of any of the various ranges recited above, for example, arange between about 0.25 mm and about 0.40 mm.

In one embodiment, A1 is about 45 degrees. An angle A1 of about 45degrees may create a desired interlocking stiffness, such that a treadblock 302 on a first side of tire sipe 304 engages the correspondingelements of tread block 302 on a second side of tire sipe 304. In oneembodiment, a thickness T1 of about 0.30 mm may create a desiredinterlocking stiffness. In another embodiment, an angle A1 of about 45degrees and a thickness T1 of about 0.30 mm may create a desiredinterlocking stiffness between opposite sides of tread block 302 oneither side of tire sipe 304. A desired interlocking stiffness may bethat stiffness that provides at least one of a desired brakingperformance, a desired tractive performance, a desired wear performance,and a desired maneuvering performance. The zig-zag shape of tire sipe304 (in a radial direction) may generate an optimal interlockingstiffness.

First angled portion 328 and fourth angled portion 334 may include aradial depth D3. Depth D3 may be any of a variety of depths as may bedesired in any of various designs of tire sipe 304. In one embodiment,depth D3 may be about 0.50 mm. In another embodiment, depth D3 may bebetween about 0.45 mm and about 0.55 mm. In another embodiment, depth D3may be between about 0.40 mm and about 0.60 mm. In another embodiment,depth D3 may be between about 0.35 mm and about 0.65 mm. In anotherembodiment, depth D3 may include a range comprising the lower and upperlimits of any of the various ranges recited above, for example, a rangebetween about 0.45 mm and about 0.60 mm.

Second angled portion 330 and third angled portion 332 may include aradial depth D4. Depth D4 may be any of a variety of depths as may bedesired in any of various designs of tire sipe 304. In one embodiment,depth D4 may be about 1.00 mm. In another embodiment, depth D4 may bebetween about 0.90 mm and about 1.10 mm. In another embodiment, depth D4may be between about 0.80 mm and about 1.20 mm. In another embodiment,depth D4 may be between about 0.70 mm and about 1.30 mm. In anotherembodiment, depth D4 may include a range comprising the lower and upperlimits of any of the various ranges recited above, for example, a rangebetween about 0.90 mm and about 1.20 mm.

Tire sipe 304 may include radially outer sipe taper portion 336.Radially outer sipe taper portion 336 may include a tapered void thatincreases in width as it progresses radially. Radially outer sipe taperportion 336 may include a lesser width at its radially innermostportion, and a greater width at its radially outermost portion. Radiallyouter sipe taper portion 336 may include a radially outer sipe width W1,and a radially outer sipe transition width W2. Width W1 may be greaterthan width W2, such that radially outer sipe taper portion 336 tapersout away from itself as it extends radially outwardly.

In one embodiment, width W1 may be about 0.60 mm, while width W2 may beabout 0.42 mm. In one embodiment, width W1 and W2 may be any of avariety of widths, as may be desired in any of various designs of tiresipe 304.

In one embodiment, width W1 may be between about 0.54 mm and about 0.66mm. In another embodiment, width W1 may be between about 0.48 mm andabout 0.72 mm. In another embodiment, width W1 may be between about 0.42mm and about 0.78 mm. In another embodiment, width W1 may have a rangecomprising the lower and upper limits of any of the various rangesrecited above, for example, a range between about 0.48 mm and about 0.78mm.

In one embodiment, width W2 may be between about 0.38 mm and about 0.46mm. In another embodiment, width W2 may be between about 0.33 mm andabout 0.50 mm. In another embodiment, width W2 may be between about 0.29mm and about 0.55 mm. In another embodiment, width W2 may have a rangecomprising the lower and upper limits of any of the various rangesrecited above, for example, a range between about 0.33 mm and about 0.55mm.

Width W2 may be about 70% of width W1. Width W1 may be about 143% ofwidth W2. In one embodiment, width W2 may be between about 65% and about75% of width W1. In another embodiment, width W2 may be between about60% and about 80% of width W1. In another embodiment, width W2 may bebetween about 55% and about 85% of width W1. In another embodiment,width W2 may be between about 60% and about 70% of width W1. In anotherembodiment, width W2 may be between about 70% and about 80% of width W1.In another embodiment, width W2 may be a percentage of width W1 within arange comprising the lower and upper limits of the various rangesrecited above, for example, a range between about 60% and about 70%.

Radially outer sipe taper portion 336 may have a depth D2. Depth D2 maybe about 1.00 mm. In one embodiment, depth D2 may be any of a variety ofdepths, as may be desired in any of various designs of tire sipe 304.Depth D2 may be about 15% of depth D1. In one embodiment, depth D2 maybe between about 10% and about 20% of depth D1. In another embodiment,depth D2 may be between about 5% and about 25% of depth D1. In anotherembodiment, depth D2 may be between about 2.5% and about 30% of depthD1. In another embodiment, depth D2 may be a percentage of depth D1within a range comprising the lower and upper limits of any of thevarious ranges recited above, for example, a range between about 5% andabout 30%.

Radially outer sipe taper portion 336 may include widths W1 and W2 thatare configured to provide adequate opening in tire sipe 304 for at leastone of snow performance and wet performance. That is, widths W1 and W2may be selected to permit a desired amount of snow and/or water to entertire sipe 304. Radially outer sipe taper portion 336 may include widthsW1 and W2 that are configured to increase strength and/or stiffness of asipe blade used to mold tire sipe 304.

Widths W1, W2, W3, and W4 may be measured substantially transversely(along the X-axis in FIG. 3 ) to the longitudinal direction of tire sipe304. For example, where tire sipe 304 extends in an axial direction,widths W1, W2, W3, and W4 may be measured along the circumferentialdirection.

FIG. 4 illustrates an elevational view of an example embodiment of atire tread block 402 having a three-dimensional tire sipe 404. Treadblock 402 may have a radially outermost portion 420. Tread block 402 mayhave a block sidewall 422.

Tire sipe 404 may include at least one laterally outermost sipe portion440. Laterally outermost sipe portion 440 may extend from at least oneblock sidewall 422. Laterally outermost sipe portion 440 may besubstantially planar. Laterally outermost sipe portion 440 may besubstantially parallel to the longitudinal axis of tire sipe 404.

Tire sipe 404 may include a sipe laterally central portion 442. Sipelaterally central portion 442 may be oriented laterally between a pairof lateral outermost sipe portions 440. Sipe laterally central portion442 may comprise a zig-zag orientation. For example, sipe laterallycentral portion 442 may comprise a plurality of angled portions,including for example, a first sipe laterally angled portion 444, asecond sipe laterally angled portion 446, a third sipe laterally angledportion 448, a fourth sipe laterally angled portion 450, and a fifthsipe laterally angled portion 452.

Each angled portion of sipe laterally central portion 442 as describedabove (first sipe laterally angled portion 444, second sipe laterallyangled portion 446, third sipe laterally angled portion 448, fourth sipelaterally angled portion 450, and fifth sipe laterally angled portion452) may be oriented at an angle A2 relative to the lateral axis of tiresipe 404. For example, where tire sipe 404 is oriented in the axialdirection (illustrated by the Y-axis), angle A2 would be measured fromthe circumferential direction (illustrated by the X-axis). Where tiresipe 404 is inclined relative to the circumferential direction of thetire, angle A2 is measured relative to the circumferential direction(illustrated by the X-axis), while adding or subtracting (depending uponwhich angled portion is being measured) the angle of tire sipe 404'sinclination.

Angle A2 may be any of a variety of angles as may be desired in any ofvarious designs of tire sipe 404. In one embodiment, angle A2 may beabout 31 degrees. In another embodiment, angle A2 may be between about26 degrees and about 36 degrees. In another embodiment, angle A2 may bebetween about 21 degrees and about 41 degrees. In another embodiment,angle A2 may be between about 16 degrees and about 46 degrees. Inanother embodiment, angle A2 may include a range comprising the lowerand upper limits of any of the various ranges recited above, forexample, a range between about 21 degrees and about 46 degrees.

Tire sipe 404 may include a radially outer sipe width W1 at radiallyoutermost block surface 420. Width W1 may be the same as width W1described above with respect to FIG. 3 .

First sipe laterally angled portion 444 and fifth sipe laterally angledportion 452 may have a lateral magnitude P1 measured along thelongitudinal axis of sipe 404. Lateral magnitude P1 may be any of avariety of lengths as may be desired in any of various designs of tiresipe 404. In one embodiment, lateral magnitude P1 may be about 2.00 mm.In another embodiment, lateral magnitude P1 may be between about 1.80 mmand about 2.20 mm. In another embodiment, lateral magnitude P1 may bebetween about 1.60 mm and about 2.40 mm. In another embodiment, lateralmagnitude P1 may be between about 1.40 mm and about 2.60 mm. In anotherembodiment, lateral magnitude P1 may include a range comprising thelower and upper limits of any of the various ranges recited above, forexample, a range between about 1.60 mm and about 2.60 mm.

At least one of third sipe laterally angled portion 448, fourth sipelaterally angled portion 450, and fifth sipe laterally angled portion452 may have an angled lateral magnitude P2 measured along thelongitudinal axis of sipe 404. Angled lateral magnitude P2 may be any ofa variety of lengths as may be desired in any of various designs of tiresipe 404. In one embodiment, angled lateral magnitude P2 may be about4.00 mm. In another embodiment, angled lateral magnitude P2 may bebetween about 3.60 mm and about 4.40 mm. In another embodiment, angledlateral magnitude P2 may be between about 3.20 mm and about 4.8 mm. Inanother embodiment, angled lateral magnitude P2 may be between about2.80 mm and about 5.20 mm. In another embodiment, angled lateralmagnitude P2 may include a range comprising the lower and upper limitsof any of the various ranges recited above, for example, a range betweenabout 3.60 mm and about 5.20 mm.

Each angled portion of sipe laterally central portion 442 may include alaterally angled portion amplitude SA1. Laterally angled portionamplitude SA1 may be measured in a substantially lateral direction oftire sipe 404. For example, where tire sipe 404 is oriented along theaxial direction (Y-axis), then laterally angled portion amplitude SA1may be measured in a circumferential direction (X-axis). Laterallyangled portion amplitude SA1 may be any of a variety of lengths as maybe desired in any of various designs of tire sipe 404. In oneembodiment, laterally angled portion amplitude SA1 may be about 1.20 mm.In another embodiment, laterally angled portion amplitude SA1 may bebetween about 1.08 mm and about 1.32 mm. In another embodiment,laterally angled portion amplitude SA1 may be between about 0.96 mm andabout 1.44 mm. In another embodiment, laterally angled portion amplitudeSA1 may be between about 0.84 mm and about 1.56 mm. In anotherembodiment, laterally angled portion amplitude SA1 may include a rangecomprising the lower and upper limits of any of the various rangesrecited above, for example, a range between about 0.96 mm and about 1.56mm.

FIG. 5 illustrates an elevational view of an example embodiment of atire tread block 502 having a three-dimensional tire sipe 504. Treadblock 502 may have a radially outermost portion 520. Tread block 502 mayhave a block sidewall 522.

Tire sipe 504 may include at least one laterally outermost sipe portion554. Laterally outermost sipe portion 554 may extend from at least oneblock sidewall 522. Laterally outermost sipe portion 554 may besubstantially planar. Laterally outermost sipe portion 554 may besubstantially parallel to the longitudinal axis of tire sipe 504.

Tire sipe 504 may include a sipe laterally central portion 556. Sipelaterally central portion 556 may be oriented laterally between a pairof lateral outermost sipe portions 554. Sipe laterally central portion556 may comprise a zig-zag orientation. For example, sipe laterallycentral portion 556 may comprise a plurality of angled portions,including for example, a first sipe laterally angled portion 558, asecond sipe laterally angled portion 560, a third sipe laterally angledportion 562, a fourth sipe laterally angled portion 564, a fifth sipelaterally angled portion 566, a sixth sipe laterally angled portion 568,and a seventh sipe laterally angled portion 570. Tire sipe 504 may besubstantially similar to tire sipe 404 described above in relation toFIG. 4 , with the exception that tire sipe 504 may include sixth andseventh laterally angled sipe portions (568 and 570).

Each angled portion of sipe laterally central portion 556 as describedabove (first sipe laterally angled portion 558, second sipe laterallyangled portion 560, third sipe laterally angled portion 562, fourth sipelaterally angled portion 564, fifth sipe laterally angled portion 566,sixth sipe laterally angled portion 568, and seventh sipe laterallyangled portion 570) may be oriented at an angle A2 relative to thelateral axis of tire sipe 504. For example, where tire sipe 504 isoriented in the axial direction (illustrated by the Y-axis), angle A2would be measured from the circumferential direction (illustrated by theX-axis). Where tire sipe 504 is inclined relative to the circumferentialdirection of the tire, angle A2 is measured relative to thecircumferential direction (illustrated by the X-axis), while adding orsubtracting (depending upon which angled portion is being measured) theangle of tire sipe 504's inclination. Angle A2 may have the same anglesrecited above with respect to angle A2 illustrated in FIG. 4 .

Tire sipe 504 may include a radially outer sipe width W1 at radiallyoutermost block surface 520. Width W1 may be the same as width W1described above with respect to FIG. 3 .

First sipe laterally angled portion 558 and seventh sipe laterallyangled portion 570 may have a lateral magnitude P1 measured along thelongitudinal axis of sipe 504. Lateral magnitude P1 may be any of avariety of lengths as may be desired in any of various designs of tiresipe 504. In one embodiment, lateral magnitude P1 may include the samevalues as described above with respect to lateral magnitude P1 in tiresipe 404 of FIG. 4 .

At least one of third sipe laterally angled portion 562, fourth sipelaterally angled portion 564, fifth sipe laterally angled portion 566,sixth sipe laterally angled portion 568, and seventh sipe laterallyangled portion 570 may have an angled lateral magnitude P2 measuredalong the longitudinal axis of sipe 504. In one embodiment, angledlateral magnitude P2 may include the same values as described above withrespect to angled lateral magnitude P2 in tire sipe 404 of FIG. 4 .

Each angled portion of sipe laterally central portion 556 may include alaterally angled portion amplitude SA1. Laterally angled portionamplitude SA1 may be measured in a substantially lateral direction oftire sipe 504. For example, where tire sipe 504 is oriented along theaxial direction (Y-axis), then laterally angled portion amplitude SA1may be measured in a circumferential direction (X-axis). Laterallyangled portion amplitude SA1 may be any of a variety of lengths as maybe desired in any of various designs of tire sipe 504. In oneembodiment, laterally angled portion amplitude SA1 may include the samevalues as described above with respect to laterally angled portionamplitude SA1 in tire sipe 404 of FIG. 4 .

In one embodiment, tire sipes 404 and 504 illustrated in FIGS. 4 and 5may include a zig-zag shape opening into radially outermost blocksurface 420 and 520. The zig-zag shape of tire sipes 404 and 504 mayallow more cutting edges in tread blocks 402 and 502. More cutting edgesmay increase at least one of snow performance and wet performance of atire including tire sipes 404 and 504. These additional cutting edgesmay exist in tread blocks 402 and 502 while maintaining requiredstiffness of tread blocks 402 and 502 for at least one of dryperformance and wear performance.

FIG. 6 illustrates a partial perspective view of an example embodimentof a tire tread block 602 having at least one three-dimensional tiresipe 604. Tread block 602 may include a radially outermost block surface620. Tread block 602 may include at least one block sidewall 622.

Tire sipe 604 may extend from at least one block sidewall 622. In oneembodiment, tire sipe 604 may include a straight sipe zone 672 extendingfor a distance from block sidewall 622 into tread block 602. In straightsipe zone 672, tire sipe 604 may be void of any zig-zag features as itextends in the radial direction. That is, in straight sipe zone 672,tire sipe 604 may have the appearance of a standard radially-orientedsipe, but may begin to zig-zag in the radial direction as tire sipe 604extends further into tread block 602 from block sidewall 622.

Tire sipe 604 may include two ends. At least one end of tire sipe 604may extend to and/or open into an edge of tread block 602. The ends oftire sipe 604 may be the axially outermost portions of tire sipe 604,where tire sipe 604 is oriented substantially axially, partiallyaxially, or axially. Straight sipe zone 672 may extend from an end oftire sipe 604. Straight sipe zone 672 may extend from an edge of treadblock 602.

Straight sipe zone 672 may be any of a variety of lengths as may bedesired in any of various designs of tire sipe 604. Straight sipe zone672 may extend from block sidewall 622 into tread block 602 for adistance of about 1.00 mm. In another embodiment, straight sipe zone 672may extend into tread block 602 between about 0.90 mm and about 1.10 mm.In another embodiment, straight sipe zone 672 may extend into treadblock 602 between about 0.80 mm and about 1.20 mm. In anotherembodiment, straight sipe zone 672 may extend into tread block 602between about 0.70 mm and about 1.30 mm. In another embodiment, straightsipe zone 672 may include a range comprising the lower and upper limitsof any of the various ranges recited above, for example, a range betweenabout 0.80 mm and about 1.30 mm.

A sipe transition zone 674 may extend into tread block 602 from straightsipe zone 672. A three-dimensional sipe zone 676 may extend fromtransition zone 674. In sipe transition zone 674, tire sipe 604 maytransition from a straight sipe in straight sipe zone 672, to athree-dimensional zig-zag sipe in a three-dimensional sipe zone 676.Three-dimensional sipe zone 676 may include radially inner and radiallyouter tapered portions, as well as a sipe radially central portioncomprising angled, zig-zag elements, all of which is illustrated in FIG.3 . Sipe transition zone 674 may represent a gradual transition betweenstraight sipe zone 672 and three-dimensional sipe zone 676.

Sipe transition zone 674 may be any of a variety of lengths as may bedesired in any of various designs of tire sipe 604. Sipe transition zone674 may extend from straight sipe zone 672 into tread block 602 for adistance of about 1.00 mm. In another embodiment, sipe transition zone674 may extend into tread block 602 between about 0.90 mm and about 1.10mm. In another embodiment, sipe transition zone 674 may extend intotread block 602 between about 0.80 mm and about 1.20 mm. In anotherembodiment, sipe transition zone 674 may extend into tread block 602between about 0.70 mm and about 1.30 mm. In another embodiment, sipetransition zone 674 may include a range comprising the lower and upperlimits of any of the various ranges recited above, for example, a rangebetween about 0.80 mm and about 1.30 mm.

As described above, three-dimensional sipe zone 676 is substantiallysimilar in structure to tire sipe 304 illustrated in FIG. 3 .

In one embodiment, tire sipe 604 has two or more ends that extend fromtwo or more block sidewalls 622. Each end of tire sipe 604 may include astraight sipe zone 672, a sipe transition zone 674, and athree-dimensional sipe zone 676. Tire sipe 604 may include two ends,wherein each end of tire sipe 604 includes straight sipe zone 672, sipetransition zone 674 extending from straight sipe zone 672, andthree-dimensional sipe zone 676 extending from sipe transition zone 674.

Straight sipe zone 672 may have any of a variety of thicknesses.Straight sipe zone 672 may have a thickness of about 0.60 mm. Straightsipe zone 672 may have a thickness of less than about 0.60 mm. Straightsipe zone 672 may have a thickness of more than about 0.60 mm.Three-dimensional sipe zone 676 may have a thickness of about 0.30 mm asdescribed above. Three-dimensional sipe zone 676 may have a thickness ofless than about 0.30 mm. Three-dimensional sipe zone 676 may have athickness of more than about 0.30 mm. Transition zone 674 may have athickness tapering from the thickness of straight sipe zone 672 to thethickness of three-dimensional sipe zone 676. In one embodiment,transition zone 674 may have a thickness tapering from about 0.60 mm toabout 0.30 mm.

Tire sipe 604 may include a straight sipe zone 672, a sipe transitionzone 674, and a three-dimensional sipe zone 676 to prevent tearing,fracture, or other destruction of the edges (where sipe 604 meets blocksidewall 622) of tread block 602 in the area of tire sipe 604. Tire sipe604 may include a straight sipe zone 672, a sipe transition zone 674,and a three-dimensional sipe zone 676 to improve the appearance andaesthetics of the laterally outer edge of tire sipe 604 (where tire sipe604 meets block sidewall 622). Tire sipe 604 may include a straight sipezone 672, a sipe transition zone 674, and a three-dimensional sipe zone676 to stiffen and/or strengthen a tire sipe blade (not shown) used tomold tire sipe 604.

It is understood that any of tire sipes 104, 204, 304, 404, 504, and 604may have a curved orientation relative to at least one of thelongitudinal axis of the tire sipes, the radial direction of the tire,and the axial direction of the tire.

It is understood that any of tire sipes 104, 204, 304, 404, 504, and 604may include a substantially planar, non-zig-zagged portion extendingfrom radially outermost block surface 120, 220, 320, 420, 520, and 620,with the three-dimensional zig-zag features illustrated in FIG. 3 as thesipe extends radially inward. That is, any of tire sipes 104, 204, 304,404, 504, and 604 may appear similar to those sipes contained inshoulder rib 108 of FIG. 1 when viewed from the surface, but wouldappear similar to those sipes contained in FIGS. 3, 4, and 5 if thesurface was cut away (along a plane parallel to the circumferentialdirection and axial direction) to reveal a sectional view of the treadblock 102, 202, 302, 402, 502, or 602 radially below the outermost blocksurface.

FIGS. 7A, 7B, 7C, and 7D illustrate an example embodiment of a tire sipeblade 780 for molding a three-dimensional tire sipe (not shown). Sipeblade 780 may include various features that are the negative of featuresto be found in any of tire sipes 104, 204, 304, 404, 504, and 604described above.

Sipe blade 780 may include a sipe radially central portion 726, whichmay include a first sipe radially angled portion 728, a second siperadially angled portion 730, a third sipe radially angled portion 732,and a fourth sipe radially angled portion 734. The various angledportions may correspond to the angled portions described above withrespect to FIG. 3 .

Sipe blade 780 may include a radially inner sipe taper portion 724. Sipeblade 780 may include a radially outer sipe taper portion 736. Radiallyinner and radially outer sipe taper portions 724 and 736 may correspondto those taper portions described above with respect to FIG. 3 .Radially outer sipe taper portion 736 may at least one of strengthensipe blade 780 and stiffen sipe blade 780. Radially inner sipe taperportion 724 may at least one of strengthen sipe blade 780 and stiffensipe blade 780. It is understood that designing sipe blade 780 with athicker portion (e.g., radially outermost portion and/or radiallyinnermost portion) may increase the strength and/or stiffness of sipeblade 780 so as to reduce the risk of deformation of sipe blade 780during molding of a tire.

Sipe blade 780 may include a laterally outermost sipe portion 754.Laterally outermost sipe portion 754 may form all or part of theintersection between a sipe and a block sidewall. Sipe blade 780 mayinclude two laterally outermost sipe portions 754.

Sipe blade 780 may include a sipe laterally central portion 756. Sipelaterally central portion 756 may include a plurality of inclinedportions oriented in a zig-zag pattern. Sipe laterally central portion756 may include a first sipe laterally angled portion 758, a second sipelaterally angled portion 760, a third sipe laterally angled portion 762,a fourth sipe laterally angled portion 764, a fifth sipe laterallyangled portion 766, a sixth sipe laterally angled portion 768, and aseventh sipe laterally angled portion 770. The various sipe laterallyangled portions may correspond to the sipe laterally angled portionsdescribed in FIGS. 4 and 5 . It is understood that sipe blade 780 andsipe laterally central portion 756 may include any number of sipelaterally angled portions.

Sipe blade 780 may include one or more of a straight sipe zone 772, asipe transition zone 774, and a three-dimensional sipe zone 776.Straight sipe zone 772, sipe transition zone 774, and three-dimensionalsipe zone 776 may correspond to straight sipe zone 672, sipe transitionzone 674, and three-dimensional sipe zone 676 illustrated in FIG. 6 .

FIG. 8 illustrates a force-displacement curve for a tire tread blockfeaturing a three-dimensional tire sipe versus a tire tread blockfeaturing a two-dimensional tire sipe. As illustrated, theforce-displacement curves illustrate the displacement of the radiallyoutermost block surface on a tread block having a three-dimensionalsipe, and a tread block having a two-dimensional sipe, across variousforce values.

The slope of each curve is representative of the stiffness of each treadblock. As illustrated, the tread block having a three-dimensional sipeincreases in stiffness under greater force. Additionally, the treadblock having a three-dimensional sipe maintains a similar stiffness at amuch greater force than the tread block having a two-dimensional sipe.

FIG. 9 illustrates a perspective view of an example embodiment of a tiretread block 902 having at least one three-dimensional tire sipe 904.Tread block 902 may include a radially outermost block surface 920 andat least one block sidewall 922.

Tire sipe 904 may include a sipe radially central portion 926 comprisinga plurality of angled elements oriented in a zig-zag pattern. Asillustrated, under the application of a shear force F, the portions oftread block 902 on either side of tire sipe 904 (through displacement ofradially outermost block surface 920) may deflect, so as to cause afirst side's angled portions to at least partially engage the secondside's angled portions. Upon engagement between the first side andsecond side, the radially outermost block surface 920 may resist furtherdisplacement, thus maintaining and/or increasing stiffness of treadblock 902.

Tire sipe 904 may include a radially outer sipe taper portion 936. Asillustrated, during deflection of tread block 902, radially outer sipetaper portion 936 remains “open” such that the first side of tread blockand the second side of tread block (bisected by tire sipe 904), remainspaced apart. Radially outer sipe taper portion 936 may be configured toremain open under deflection of tread block 902 of a tire to permit atleast one of: increased edge engagement with roadway, introduction ofsnow into tire sipe 904, and introduction of a liquid (such as water)into tire sipe 904.

During deflection of tread block 902 of a tire under shear force F, atleast one contact portion 996 may remain in contact with a roadway,while at least one liftoff portion 998 may lift out of contact with aroadway. As illustrated, tread block 902 may be broken into subportionsseparated by tire sipes 904. Each subportion may include a contactportion 996 and a liftoff portion 998. As illustrated, contact portion996 of at least one subportion may be larger in area than liftoffportion 998. As such, tread block 902 as a whole may include a greaterarea in contact with a roadway than the area lifted out of contact fromthe roadway. As a result, at least one of traction, braking, andhandling of a tire utilizing tread block 902 may be improved.

FIG. 10 illustrates a perspective view of a prior art tire tread block1090 having at least one two-dimensional tire sipe 1092. Two-dimensionaltire sipes 1092 may extend into tread block 1090 from a block sidewall1094.

As illustrated, tread block 1090 may be divided into subportionsseparated by two-dimensional tire sipes 1092. Upon the application of ashear force F to tread block 1090, the subportions may deflect,resulting in a contact portion 1096 and a liftoff portion 1098 in eachsubportion. As illustrated, contact portion 1096 may include an areaabout the same as, or even less than, liftoff portion 1098 within asubportion. As such, tread block 1090 as a whole may include a lesserarea in contact with a roadway than the area lifted out of contact fromthe roadway. As a result, at least one of traction, braking, andhandling of a tire utilizing tread block 1090 may be degraded relativeto tread block 902 of FIG. 9 .

FIG. 11 illustrates a graph comparing various properties of a tireutilizing various tire sipe styles. As illustrated, the variousproperties of a tire utilizing three-dimensional tire sipes,particularly a three-dimensional tire sipe having a radially inner sipetaper portion and a radially outer sipe taper portion, performs at leastas well and in many instances significantly better than a tire utilizingtwo-dimensional tire sipes and a control tire.

Specifically, a tire utilizing three-dimensional tire sipes performedbetter than both the control tire and a tire utilizing two-dimensionaltire sipes in the following tests: cornering coefficient, snow braking,snow acceleration, snow lateral traction, tire wear, wet roadway laptime, and dry peak friction coefficient.

To the extent that the term “includes” or “including” is used in thespecification or the claims, it is intended to be inclusive in a mannersimilar to the term “comprising” as that term is interpreted whenemployed as a transitional word in a claim. Furthermore, to the extentthat the term “or” is employed (e.g., A or B) it is intended to mean “Aor B or both.” When the applicants intend to indicate “only A or B butnot both” then the term “only A or B but not both” will be employed.Thus, use of the term “or” herein is the inclusive, and not theexclusive use. See Bryan A. Garner, A Dictionary of Modern Legal Usage624 (2d. Ed. 1995). Also, to the extent that the terms “in” or “into”are used in the specification or the claims, it is intended toadditionally mean “on” or “onto.” To the extent that the term“substantially” is used in the specification or the claims, it isintended to take into consideration the degree of precision available orprudent in manufacturing. To the extent that the term “selectively” isused in the specification or the claims, it is intended to refer to acondition of a component wherein a user of the apparatus may activate ordeactivate the feature or function of the component as is necessary ordesired in use of the apparatus. To the extent that the term“operatively connected” is used in the specification or the claims, itis intended to mean that the identified components are connected in away to perform a designated function. As used in the specification andthe claims, the singular forms “a,” “an,” and “the” include the plural.Finally, where the term “about” is used in conjunction with a number, itis intended to include ±10% of the number. In other words, “about 10”may mean from 9 to 11. Cartesian coordinates referenced herein areintended to comply with the SAE tire coordinate system.

As stated above, while the present application has been illustrated bythe description of embodiments thereof, and while the embodiments havebeen described in considerable detail, it is not the intention of theapplicants to restrict or in any way limit the scope of the appendedclaims to such detail. Additional advantages and modifications willreadily appear to those skilled in the art, having the benefit of thepresent application. Therefore, the application, in its broader aspects,is not limited to the specific details, illustrative examples shown, orany apparatus referred to. Departures may be made from such details,examples, and apparatuses without departing from the spirit or scope ofthe general inventive concept.

The invention claimed is:
 1. A tire tread comprising a sipe, comprising:a radially inner sipe taper portion having a radially innermost sipewidth W3 and a radially inner sipe transition width W4, wherein theradially innermost sipe width W3 is greater than the radially inner sipetransition width W4; a radially outer sipe taper portion having aradially outer sipe width W1 and a radially outer sipe transition widthW2, wherein the radially outer sipe width W1 is greater than theradially outer sipe transition width W2; a sipe radially central portionhaving a plurality of individual sipe radially angled portions orientedin a zig-zag pattern, wherein the sipe radially central portion isoriented radially between the radially inner sipe taper portion and theradially outer sipe taper portion, and wherein each of the sipe radiallyangled portions are oriented at an angle A1 relative to thecircumferential direction of the tire, wherein the angle A1 is between36 degrees and 54 degrees; wherein the sipe includes two laterally outeredges; and wherein each laterally outer edge of the tire sipe includes astraight sipe zone, a sipe transition zone extending from the straightsipe zone, and a three-dimensional sipe zone extending from the sipetransition zone.
 2. The tire tread of claim 1, wherein: the tire sipehas a depth D1, the radially outer sipe taper portion has a depth D2,and the depth D2 is 15% of the depth D1.
 3. The tire tread of claim 1,wherein: the tire sipe has a depth D1, the radially inner sipe taperportion has a depth D5, and the depth D5 is 40% of the depth D1.
 4. Thetire tread of claim 1, wherein the radially outer sipe taper portion isformed by two opposing inclined walls, wherein a first of the twoopposing inclined walls is inclined in a first direction relative to aradial direction of the tire tread, wherein a second of the two opposinginclined walls is inclined in a second direction relative to the radialdirection of the tire tread, and wherein the first direction and thesecond direction are opposite one another.
 5. The tire tread of claim 1,wherein the radially inner sipe taper portion is formed by two opposinginclined walls, wherein a first of the two opposing inclined walls isinclined in a first direction relative to a radial direction of the tiretread, wherein a second of the two opposing inclined walls is inclinedin a second direction relative to the radial direction of the tiretread, and wherein the first direction and the second direction areopposite one another.
 6. The tire tread of claim 1, wherein the sipeincludes two laterally outermost sipe portions that are parallel to alongitudinal axis of the sipe, and a laterally central portion betweenthe two laterally outermost sipe portions, wherein the laterally centralportion comprises a plurality of angled portions forming a zig-zagshape.
 7. A tire tread comprising a sipe, comprising: a radially innersipe taper portion having a radially innermost sipe width W3 and aradially inner sipe transition width W4, wherein the radially innermostsipe width W3 is greater than the radially inner sipe transition widthW4; a sipe radially central portion having a plurality of individualsipe radially angled portions oriented in a zig-zag pattern, wherein thesipe radially central portion is oriented radially outwardly of theradially inner sipe taper portion, and wherein each of the sipe radiallyangled portions are oriented at an angle A1 relative to thecircumferential direction of the tire, wherein the angle A1 is between36 degrees and 54 degrees; wherein the sipe includes two laterally outeredges; and wherein each laterally outer edge of the tire sipe includes astraight sipe zone, a sipe transition zone extending from the straightsipe zone, and a three-dimensional sipe zone extending from the sipetransition zone.
 8. The tire tread of claim 7, further comprising aradially outer sipe taper portion having a radially outer sipe width W1and a radially outer sipe transition width W2, wherein the radiallyouter sipe width W1 is greater than the radially outer sipe transitionwidth W2, and wherein the radially outer sipe taper portion is orientedradially outwardly of the sipe radially central portion.
 9. The tiretread of claim 7, wherein: the tire sipe has a depth D1, the radiallyinner sipe taper portion has a depth D5, and the depth D5 is 40% of thedepth D1.
 10. The tire tread of claim 7, wherein the radially inner sipetaper portion is formed by two opposing inclined walls, wherein a firstof the two opposing inclined walls is inclined in a first directionrelative to a radial direction of the tire tread, wherein a second ofthe two opposing inclined walls is inclined in a second directionrelative to the radial direction of the tire tread, and wherein thefirst direction and the second direction are opposite one another. 11.The tire tread of claim 7, wherein the sipe includes two laterallyoutermost sipe portions that are parallel to a longitudinal axis of thesipe, and a laterally central portion between the two laterallyoutermost sipe portions, wherein the laterally central portion comprisesa plurality of angled portions forming a zig-zag shape.
 12. The tiretread of claim 8, wherein: the tire sipe has a depth D1, the radiallyouter sipe taper portion has a depth D2, and the depth D2 is 15% of thedepth D1.
 13. The tire tread of claim 8, wherein the radially outer sipetaper portion is formed by two opposing inclined walls, wherein a firstof the two opposing inclined walls is inclined in a first directionrelative to a radial direction of the tire tread, wherein a second ofthe two opposing inclined walls is inclined in a second directionrelative to the radial direction of the tire tread, and wherein thefirst direction and the second direction are opposite one another.
 14. Atire tread comprising a sipe, comprising: a radially outer sipe taperportion having a radially outer sipe width W1 and a radially outer sipetransition width W2, wherein the radially outer sipe width W1 is greaterthan the radially outer sipe transition width W2; wherein the radiallyouter sipe taper portion is formed by two opposing inclined walls;wherein a first of the two opposing inclined walls is inclined in afirst direction relative to a radial direction of the tire tread;wherein a second of the two opposing inclined walls is inclined in asecond direction relative to the radial direction of the tire tread; andwherein the first direction and the second direction are opposite oneanother; a sipe radially central portion having a plurality ofindividual sipe radially angled portions oriented in a zig-zag pattern,wherein the sipe radially central portion is oriented radially inwardlyof the radially outer sipe taper portion, and wherein each of the siperadially angled portions are oriented at an angle A1 relative to thecircumferential direction of the tire, wherein the angle A1 is between36 degrees and 54 degrees; wherein the sipe includes two laterally outeredges; and wherein each laterally outer edge of the tire sipe includes astraight sipe zone, a sipe transition zone extending from the straightsipe zone, and a three-dimensional sipe zone extending from the sipetransition zone.
 15. The tire tread of claim 14, further comprising aradially inner sipe taper portion having a radially innermost sipe widthW3 and a radially inner sipe transition width W4, wherein the radiallyinnermost sipe width W3 is greater than the radially inner sipetransition width W4, and wherein the radially inner sipe taper portionis oriented radially inwardly of the sipe radially central portion. 16.The tire tread of claim 14, wherein: the tire sipe has a depth D1, theradially outer sipe taper portion has a depth D2, and the depth D2 is15% of the depth D1.
 17. The tire tread of claim 14, wherein theradially inner sipe taper portion is formed by two opposing inclinedwalls, wherein a first of the two opposing inclined walls is inclined ina first direction relative to a radial direction of the tire tread,wherein a second of the two opposing inclined walls is inclined in asecond direction relative to the radial direction of the tire tread, andwherein the first direction and the second direction are opposite oneanother.
 18. The tire tread of claim 14, wherein the sipe includes twolaterally outermost sipe portions that are parallel to a longitudinalaxis of the sipe, and a laterally central portion between the twolaterally outermost sipe portions, wherein the laterally central portioncomprises a plurality of angled portions forming a zig-zag shape. 19.The tire tread of claim 15, wherein: the tire sipe has a depth D1, theradially inner sipe taper portion has a depth D5, and the depth D5 is40% of the depth D1.